Propagation of a light beam in optical fiber tapers depends on few parameters like diameter of a taper waist region, adiabatic or non-adiabatic shape of a whole, as well as boundary condition connected with refractive index surrounding the taper. As external materials many mixtures can be used allowing to manufacture different applications [1-3]. In this work we applied liquid crystals’ medium due to its optical properties - anisotropic as a cladding for the manufactured taper. Properties of liquid crystals can be modified by electric or magnetic fields, as well as by temperature change. These features make liquid crystal fibers very important for optical applications. In this work we have built an optical cell which consists of a liquid crystals’ mixture of 1550C1 [4]. The applied taper can be described by the following parameters: diameters of 10+/- 0.5 μm, losses lower than 0.5 dB in visible range, manufactured on FOTET. The tapered fiber was put in a liquid-crystal cell made of two tin oxide coated glass plates separated by spacers. The value of the used electric field was contained in the range of 0V - 160V. This experiment demonstrates ability of changing optical transmission in a tapered fiber immersed in a liquid-crystal medium. The range of optical transmission observation was between 500-700 nm which was connected with an LC transmission. Also, were performed measurements of influence of temperature in the range of 20-80°C on the proposed device. For temperature higher than 50°C, increased optical power propagating in the tapered fiber was observed.
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